1. Field of the Invention
The present invention relates to a surveying system. In particular, it relates to a surveying instrument or system, including a total station, an electronic tacheometer, or the like, that is able to measure an angle and a distance relating to a measurement point.
2. Description of the Related Art
Generally, a surveying operation requires at least two persons. Namely, one holds a target, such as a prism or the like, at a measurement point, while the other person operates a surveying instrument. In the surveying operation, in order to obtain measurement data for a plurality of measurement points, the person with the target should move to each of the measurement points, and the other person should sight the surveying instrument to the target, each time the target moves to a measurement point. Therefore, the conventional surveying operation is quite cumbersome and requires at least two people and a lot of time, so it is inefficient and expensive. Recently, a non-prism-type surveying instrument, which requires no target, has been developed. With the non-prism-type surveying instrument, the person who carries the target can be excluded and the surveying can be carried out by a single person who operates the surveying instrument, so that the efficiency of the surveying operation is improved. However, even when using the non-prism-type surveying instrument, the operator should still carry out sighting operations for each of the measurement points. This becomes extremely cumbersome and requires time particularly when the number of measurement points is large, such as when estimating the volume of a basin or hollow ground to be buried.